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                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549

                              --------------------

                                   FORM N-PX

                              --------------------

                    ANNUAL REPORT OF PROXY VOTING RECORD OF
                   REGISTERED MANAGEMENT INVESTMENT COMPANIES

                  Investment Company Act file number 811-04096

                              --------------------

                           MFS MUNICIPAL SERIES TRUST
               (Exact name of registrant as specified in charter)

                              --------------------

              111 Huntington Avenue, Boston, Massachusetts 02199
              (Address of principal executive offices) (Zip code)

                              --------------------

                                Susan S. Newton
                    Massachusetts Financial Services Company
                             111 Huntington Avenue
                          Boston, Massachusetts 02199
                    (Name and address of agents for service)

      Registrant's telephone number, including area code: (617) 954-5000

                              --------------------

                       Date of fiscal year end: March 31

             Date of reporting period: July 1, 2012 - June 30, 2013

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ITEM 1.  PROXY VOTING RECORD.



******************************* FORM N-Px REPORT *******************************

ICA File Number: 811-04096
Reporting Period: 07/01/2012 - 06/30/2013
MFS Municipal Series Trust









======================= MFS Alabama Municipal Bond Fund ========================

There is no proxy voting activity for the fund, as the fund did not hold any
votable positions during the reporting period.



======================= MFS Arkansas Municipal Bond Fund =======================

There is no proxy voting activity for the fund, as the fund did not hold any
votable positions during the reporting period.



====================== MFS California Municipal Bond Fund ======================

There is no proxy voting activity for the fund, as the fund did not hold any
votable positions during the reporting period.


======================= MFS Georgia Municipal Bond Fund ========================

There is no proxy voting activity for the fund, as the fund did not hold any
votable positions during the reporting period.



======================= MFS Maryland Municipal Bond Fund =======================

There is no proxy voting activity for the fund, as the fund did not hold any
votable positions during the reporting period.



==================== MFS Massachusetts Municipal Bond Fund =====================

There is no proxy voting activity for the fund, as the fund did not hold any
votable positions during the reporting period.



===================== MFS Mississippi Municipal Bond Fund ======================

There is no proxy voting activity for the fund, as the fund did not hold any
votable positions during the reporting period.



========================== MFS Municipal Income Fund ===========================

There is no proxy voting activity for the fund, as the fund did not hold any
votable positions during the reporting period.



======================= MFS New York Municipal Bond Fund =======================

There is no proxy voting activity for the fund, as the fund did not hold any
votable positions during the reporting period.



==================== MFS North Carolina Municipal Bond Fund ====================

There is no proxy voting activity for the fund, as the fund did not hold any
votable positions during the reporting period.



===================== MFS Pennsylvania Municipal Bond Fund =====================

There is no proxy voting activity for the fund, as the fund did not hold any
votable positions during the reporting period.



==================== MFS South Carolina Municipal Bond Fund ====================

There is no proxy voting activity for the fund, as the fund did not hold any
votable positions during the reporting period.



====================== MFS Tennessee Municipal Bond Fund =======================

There is no proxy voting activity for the fund, as the fund did not hold any
votable positions during the reporting period.



======================= MFS Virginia Municipal Bond Fund =======================


JAMES CITY CNTY VA ECONOMIC DEV AUTH RESIDENTIAL CARE FAC RE

Ticker:                      Security ID:  47029WAW7
Meeting Date: MAY 08, 2013   Meeting Type: Written Consent
Record Date:  APR 01, 2013

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     To Accept the Plan                      None      For          Management




==================== MFS West Virginia Municipal Bond Fund =====================

There is no proxy voting activity for the fund, as the fund did not hold any
votable positions during the reporting period.
========== END NPX REPORT



                                   SIGNATURES

Pursuant to the requirements of the Investment Company Act of 1940, the
registrant has duly caused this report to be signed on its behalf by the
undersigned, thereunto duly authorized.

Registrant: MFS MUNICIPAL SERIES TRUST

By (Signature and Title):  JOHN M. CORCORAN*
                           ----------------------------------------------
                           John M. Corcoran, Principal Executive
                           Officer & President

Date: August 16, 2013

*By (Signature and Title)  /s/ Susan S. Newton
                           ----------------------------------------------
                           Susan S. Newton, as attorney-in-fact

*    Executed by Susan S. Newton on behalf of John M. Corcoran pursuant to a
     Power of Attorney dated July 8th, 2013. (1)

(1)  Incorporated by reference to MFS Municipal Series Trust (File Nos. 2-92915
     and 811-4096) Post-Effective Amendment No. 56 filed with the SEC via EDGAR
     on July 26, 2013.